Understanding Our Changing Climate

The Cowichan Region's climate has large variations over short distances because of complex geography. Areas with the least precipitation include the east coast of the region. The highest amounts of precipitation occur on the west coast of the region and upland areas in the interior of the Island. The projected impacts to our climate over the next century include an increase in temperature, an increase in precipitation, a decrease in snowpack through much of the region, and an increase in sea level.

Climate models for the South Coast of BC project warming throughout the 21st century for all seasons. Summer is projected to warm slightly more than other seasons, by 2.0 oC by the 2050s and 3.1 oC by the 2080s.
A seasonal increase in hot and dry conditions would increase the possibility of water shortages, increase plant and livestock stress, and place thermal stress on fish and their habitats.

A change in agricultural productivity could result from a longer growing season, seasonally waterlogged soil, and decreased water availability. New crops and varieties may become viable. Animal and plant species are likely to migrate in response to warming. If the dry season increases in length, this could increase forest fire severity.

Fall, winter, and spring precipitation is expected to increase by about 10% by the 2080s while a decrease of over 10% in summer precipitation is projected.

Both river flooding and ocean storm surge events may increase in frequency and magnitude; stream bank erosion and strain on flood protection infrastructure may increase. Storm surge events may impact farmland in coastal and delta areas through soil salination, inundation, and the salination of irrigation water sources. Increasing storm surges could require new design guidelines for flood control levels.

Warming will decrease snowpack throughout much of the region. Increases to high-intensity precipitation and seasonal moisture variability affect a variety of habitats. There could be a transition to rainfall-dominant watersheds, causing an increased need for water conservation and storage.

Current estimates of mean sea level rise by 2100 for the east coast of Vancouver Island are an increase of 80 cm. The CVRD has developed detailed sea level rise impact mapping for the east coast region. Potential impacts of sea level rise include:

More frequent and extreme high water levels in coastal areas

Increased erosion and flooding

Increased risk to coastal infrastructure, as well as increased maintenance and repair costs